Exelixis, Inc. has submitted an investigational new drug application (IND) to the U.S. Food and Drug Administration (FDA) for XL999, a proprietary novel anticancer compound.
Preclinical studies with XL999 have demonstrated potent inhibition in vivo against multiple receptor tyrosine kinases (RTKs) that are implicated in tumor angiogenesis, or the development and maintenance of tumor vasculature. Pending clearance by the FDA, the company intends to initiate a Phase 1 clinical trial.
XL999 is one of several Spectrum Selective Kinase Inhibitors(TM) (SSKI) in Exelixis' product pipeline. Each SSKI has a different RTK inhibition spectrum, and each has the potential to achieve efficacy through simultaneous inhibition of multiple RTKs. Preclinical studies have shown that XL999 simultaneously inhibits the FGFR, VEGFR, PDGFR and Flt3 RTKs with high levels of potency and demonstrates excellent activity in target-specific cellular functional assays. XL999 has demonstrated potent anti-tumor activity in a variety of preclinical models of solid tumors as well as a Flt3-driven model of leukemia.
"This IND application is the second we have filed this year, which is the direct result of the productivity of our R&D groups," said George A. Scangos, Ph.D., president and chief executive officer. "Together with XL119, which recently began a pivotal Phase 3 study, XL784, which has successfully completed a Phase 1 study, XL647, which has begun a Phase 1 study, and a rich portfolio of pre-clinical development compounds, XL999 is part of a growing, high-quality pipeline of compounds that we intend to advance rapidly into and through clinical trials. Our goal is to leverage our significant expertise in biology, drug discovery, and development to generate a diverse portfolio of anti-cancer compounds with substantial therapeutic and commercial potential. This IND application is one more sign that we are executing on our vision of becoming a major cancer therapeutics company."
The Phase 1 clinical trial of XL999 will be an open-label, dose escalation study conducted in cancer patients. The study is designed to measure the safety, tolerability, pharmacokinetics, pharmacodynamics and biological activity of XL999 following a single intravenous administration. The study will be conducted at a major medical center in the United States.